If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

S70 Alpha/Alpha II/Alpha III baffle layout?

Hey, I seem to have misplaced the picture I had, of a JBL S70 Alpha system, with the grille off. I know the mid and tweeter are near the center top, in a vertical stack, with the woofer and passive radiator "flanking" them but near the bottom of the cabinet. However, I don't know the exact proportions.

Pretty much any picture would be OK- I just need proportions. I can figure out the scale I need, and get exact measurements from that, if I just know where everything is, in relation to everything else...

Anyone know of a picture around anywhere? I haven't been able to find one. I'm going to check Ebay completed auctions next...

Yep! With one alteration- my passive radiators are PR300s, instead of PR12s. The PR300 should be capable of a bit more volume displacement than the PR12s.

I've actually got all the parts, in functional condition now. I got a mismatched pair of L100s which provided 123A-1s, a LE5-2 frame, a LE20 and crossover boards, found a pair of frames and reconed a pair of PR300s (with a 128H cone and spider, and a 3" diameter 1/2" thick round slug of MDF with a bolt in the center for a "voice coil", ala the original), traded Don W. for a pair of LE20s (of which one exactly matches the one from the early L100) and another LE5-2 frame, and just today reconed the LE5-2s.

I think I may build a more "contemporary" styled cabinet, as well as changing the PR... I'm still undecided on cosmetics, but it may wind up looking a bit more "studio-monitorish" than the original "low-boy console" look of the original. The construction may take a while, as I'm building, at last count, 6 different loudspeaker projects at once right now, one of which (a double-18", double 6.5/horn WWMTM PA speaker) has a very definite "drop-dead" date. But the L70 is MUCH more likely to get attention than before, since EVERYTHING is now on-hand for it!